Q: TL431BQDBZRQ1 Voltage Raring and Protection circuits by 752052

Questions for TL431BQDBZRQ1

Q1: What's the maxim voltage rating between Ref and Anode?
Q2: Are there any protection diode or protection circuit for Ref Pin?
      Please let me know detail of internal circuit of Ref pin
Q3: Is there any protection circuit for ESD?
      Is TL431 guaranteed for ESD rating?
      How about spec.?
Q4: What's the maxim voltage rating between Cathode to Ref?
      Are there any protection circuit between Cathode and Ref pin?

Best regards,


Q: Re: TL431BQDBZRQ1 Voltage Raring and Protection circuits by 9125

 

Q1: What's the maxim voltage rating between Ref and Anode?

Answer: In forward bias, between Ref and anode are 2 PN junction in series with 3.28K and 2.4K//7.2K. It is current driven input and the absolute max forward current is 10mA. I believe voltage rating is not accurate because of these resistors tolerance. Check datasheet internal circuit.


Q2: Are there any protection diode or protection circuit for Ref Pin?
      Please let me know detail of internal circuit of Ref pin

Answer: In reverse bias, between Ref and anode are 2 PN junction and the absolute max reverse current is 50uA. Check datasheet internal circuit.


Q3: Is there any protection circuit for ESD?
      Is TL431 guaranteed for ESD rating?
      How about spec.?

Answer: HBM = 2.5KV, CDM = 1KV and MM = 200V. It is in the datasheet.


Q4: What's the maxim voltage rating between Cathode to Ref?
      Are there any protection circuit between Cathode and Ref pin?

Answer: between Cathode and Ref is NP junction (collector to base of bipolar transistor). I believe the breakdown is 37V like Cathode to Anode.

Regards, Mahmoud